LUSH-PEDIA

To export list or document library nintex workflow using NWAdmin command: NWAdmin.exe -o ExportWorkflow -siteUrl "http://sv01appmoss01:1997/sites/siteCollection" -workflowName "WF Name" -filename "C:\test.nwf" -list "Shared Documents" -username "username" -password "12345" -domain "domainname" -workflowtype list

https://community.nintex.com/community/support/blog/2014/10/02/how-to-aggregate-uls-logs-for-nintex-support 

The solution is to run database update for Nintex Workflow in SharePoint Central Administration

Problem: The form cannot be submitted to the specified SharePoint list or document library. The SharePoint location may be read-only or you may not have permissions to access it. OR  The workflow could not update the item, possibly because one or more columns for the item require a different type of information. Solution: Go to the List Settings then Advanced Settings and then set /verify options for Read Access / Edit Access.

http://sharepointpolice.com/blog/2010/04/30/%E2%80%9Cthe-form-cannot-be-displayed-because-session-state-is-not-available%E2%80%9D-in-sharepoint/